If sin A 12 A in quadrant IV what is tan 2A write your answ
     If sin A = -1/2, A in quadrant IV, what is tan 2A?  (write your answer as a fraction or whole number with NO SPACES, i.e., -sqrt(2)/2)  Rewrite as a function of a single angle. Use * for degrees.  sqrt((1+cos 76*)/2)   
  
  Solution
tan 2A = 2tanA/ (1tan^2 A)
sinA = -1/2
so A = 360* - 30*
A =330* (* degree)
so tan(A) =tan(330)
= -1/sqrt(3)
tan 2A = 2tanA/ (1tan^2 A)
tan2A = 2. -1/sqrt(3) / (1 - (1/sqrt(3)^2 )
= -2/sqrt(3) / (1-1/3)
= -2/sqrt(3)/2/3
= -3/sqrt(3)
= -sqrt(3)
2).
sqrt[ (1+cos76*)/2) = sqrt[ (1 +cos(90 - 14) )/2 ]
but cos(90-x) =sinx
so sqrt[ (1+cos76*)/2) = sqrt( (1+sin14*)/2 )

